National Hydrography Dataset

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The National Hydrography Dataset (NHD) is a United States-wide hydrography dataset produced by the United States Geological Survey (USGS). This dataset includes lakes, ponds, rivers, streams, and other features related to water such as dams. As a product of the US Government, the dataset is in the public domain. Due to this and the general high quality of the data, some regard it as suitable for import into OpenStreetMap, and some of those people have proceeded with importing. This page details the process, progress, and mapping as the dataset is imported.

Import Process

Imports and automated edits should only be carried out by those with experience and understanding of the way the OpenStreetMap community creates maps, and only with careful planning and consultation with the local community. See Import/Guidelines and Automated Edits code of conduct for more information. Imports/automated edits which do not follow these guidelines might be reverted!

Please try to limit duplicate nodes/ways in your uploads. One solution is to alter scripts so that they make one file per feature class (by making large numbers of points per file) (waterbody, area, etc.) per subbasin. Merge these files in Josm and then remove duplicate nodes. This also provides an opportunity to check whether any features have been previously uploaded. Large files, which take along time to merge in JOSM, can also be merged together with Osmosis. Once you have the merged file, you can upload from JOSM as it will automatically split these large files into appropriately sized changesets.

Get the data

Geo Extract Options

Obtain High Resolution Shapefiles from the NHD web site by using the NHD Geodatabase Viewer or go to the NHD Geodatabase, which has a simpler interface. Read the "How to extract" instruction on the left, pop-ups must be enabled for the site.

Note: Some NHD items will appear in multiple adjacent sub-basin extracts. If possible, either load in an editor and preview for river bodies extending outside the map line, or test for duplicate NHD:ComID values in separate uploads.

The NHD files are no longer shapefiles but are Personal GDB or File GDB files. These files can be difficult to process with open source tools but QuantumGIS and gdal have support for Personal GDB files with the default windows builds.

Java

Projection

Default projection is 4269: NAD83

Attribute to tag mapping

Contained below are some possible mapping schemes, that is what OSM tags to assign to an object based on the attributes of the object in the original Shapefile. Note that there is no one unified scheme, and it can differ from one area to the next.

None of the three mappings listed here is up to date with the latest NHD files. If you wish to propose an import you may need to produce your own.

Mapping 3: NHD Rules

Feature codes observed in the NHD

Basins and per-basin sign-ups

The following tables list the 347 basins in the lower-48, with links to the approximate center of the basins on The Map, and a column to sign up on a per-basin basis. Todo: how to handle partial-basin signups.